What is String in Python ? | Types of String | Basic String Operations and Methods in Python

What is String in Python?

• A string in Python is a sequence of characters, like letters, numbers, and symbols, enclosed in quotes.
• Strings are used to represent text.

Example:

# Single quote string
single_quote_string = 'Hello, World!'

# Double quote string
double_quote_string = "Python programming is easy."

# Multi-line string
multi_line_string = """This is a string
that extends across multiple lines."""

# Printing the strings
print(single_quote_string )
print(double_quote_string )
print(multi_line_string)

Output:

Hello, World!
Python programming is easy.
This is a string
that extends across multiple lines.

Basic String Operations and Methods in Python:

Concatenation:

• Combining two or more strings into one.

Example:

str1 = "Hello"
str2 = "World"
result = str1 + " " + str2
print(result)   # Output: Hello World

Repetition:

• Repeating a string multiple times.

Example:

str1 = "Python! "
result = str1 * 3
print(result)   # Output: Python! Python! Python!

Indexing:

• Accessing individual characters in a string using their index (starting from 0).

Example:

str1 = "Python"
print(str1[0])   # Output: P
print(str1[1])   # Output: y
print(str1[-1])  # Output: n (last character)

Slicing:

• Slicing extracts a portion of a string by specifying a range of indices.

Example:

str1 = "Python Programming"

# Extracting a substring from index 0 to 5 (not including 6)
print(str1[0:6])      # Output: Python

# Extracting a substring from index 7 to the end
print(str1[7:])       # Output: Programming

# Extracting every second character from the entire string
print(str1[::2])      # Output: Pto rgamn

# Extracting a substring from index -11 to -1 (not including -1)
print(str1[-11:-1])   # Output: Programming

# Reversing the string
print(str1[::-1])     # Output: gnimmargorP nohtyP

.upper() Method:

• Converts all characters in a string to uppercase.

Example:

str1 = "hello"
result = str1.upper()
print(result)   # Output: HELLO

.lower() Method:

• Converts all characters in a string to lowercase.

Example:

str1 = "HELLO"
result = str1.lower()
print(result)   # Output: hello

.replace() Method:

• Replaces occurrences of a substring with another substring.

Example:

str1 = "Hello World"
result = str1.replace("World", "Python")
print(result)   # Output: Hello Python

.split() Method:

• Splits a string into a list of substrings based on a delimiter.

Example:

str1 = "Python is simple"
result = str1.split(" ")
print(result)   # Output: ['Python', 'is', 'simple']